It is well known that various olefins can be reacted with carbon monoxide and hydrogen so as to be converted into corresponding aldehydes and/or alcohols. These reactions are often referred to as oxo or hydroformylation reactions. It is also well known that such hydroformylation reactions are catalyzed by a select group of catalytic systems which include the metals of rhodium, ruthenium, rhenium cobalt, platinum, palladium, osmium, and iridium. However, catalysts containing such valuable nobel metals must be recovered from the products of reaction and recycled to the reaction zone. Such recovery is a relatively expensive operation and greatly increases the costs of the process. Insolubilized catalysts, such as the one disclosed herein, can be separated from reaction products by simple filtration. A preferred embodiment for effecting catalyst separation includes utilizing the supported catalyst in the form of screens, webs, cloths, etc. which can easily be loaded and/or unloaded into or from a commercial reactor. This is an improvement over other catalyst supports utilized in the past which have generally taken the form of polymer beads, gels, inorganic beads, spheres, cylinders, irregular granules, etc. which may require careful loading to avoid uneven pressure drops due to uneven pellet distribution, or to build up of fines from crushed pellets, etc.
Additionally, the ability of polybenzimidazole to form a stable insoluble complex with rhodium carbonyl chloride may be utilized to achieve recovery of the rhodium metal from solution.
It is an object of the present invention to provide an improved hydroformylation process which utilizes a polybenzimidazole (PBI) fiber supported rhodium carbonyl complex.
It is another object of the present invention to provide an improved catalytic system to be utilized in hydroformylation reactions which may be readily separated from the reaction products and reused repeatedly.
It is a further object of the present invention to provide a method of making a polybenzimidazole fiber supported rhodium carbonyl complex to be utilized in hydroformylation reactions.
It is a further object of the present invention to provide a method of making a supported catalyst that can be fabricated in the form of screens, cloths, webs, and hollow tubes.
It is still a further object of the present invention to provide a means for recovering rhodium metal from solution.
These and other objects, as well as the scope, nature, and utilization of the invention, will be apparent to those skilled in the art from the following description and appended claims.